In this review, we will be comparing Crystal 4.2 and S20, two Passive Bookshelf speakers from Wharfedale and Polk Audio. Let's have a brief look at the main features
of Wharfedale Crystal 4.2 and Polk S20 first before getting into our more
detailed comparison.
What size room are the Wharfedale Crystal 4.2 and Polk S20 speakers good for?
The size of the room in which you are planning to use these loudspeakers is an important decision factor. Here we have compared their suitability to various sizes of environments considering their size and max power parameters:
In the following sections, we will get into more detail in order to better understand how the Wharfedale Crystal 4.2 and Polk S20 compare and hopefully end up with enough arguments to decide which one of these loudspeakers is the better choice for you.
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Drivers
Both Crystal 4.2 and S20 are 2-way speakers.
Driver |
Wharfedale Crystal 4.2 |
Polk S20 |
Driver Setup
|
2-way
|
2-way
|
Tweeter
|
1-inch
|
1-inch
|
Midrange
|
- |
- |
Woofer
|
1 x 5-inch
|
1 x 6.5-inch
|
Crystal 4.2 features a 1" Soft-dome Tweeter and 1 x 5" Woven Kevlar Woofer . On the other hand, the S20 features a 1" Terylene Soft-Dome Tweeter and 1 x 6.5" Mica-reinforced polypropylene Woofer with a Crossover frequency at 2500Hz.
Frequency Response
Crystal 4.2 has a frequency range of 60-20k Hz whereas S20 has a frequency range of 39-40k Hz. With a minimum frequency of 39Hz, the S20 can go significantly deeper on the low side and provide stronger bass compared to the Crystal 4.2's min frequency of 60Hz.
Below graphs depict how these two speakers compare with the max, min and average values of the Min and Max Frequencies of other speakers in the Bookshelf class in our database.
Low Frequency
Bookshelf Speakers
High Frequency
Bookshelf Speakers
None of these speakers achieves full range experience which is commonly agreed as 20Hz-20kHz. In order to achieve lower lows / deeper bass, we recommend you pair these with a subwoofer. Visit our Powered Subwoofers section to find out more about the available options.
Impedance and Sensitivity
Crystal 4.2 and S20 have the same Impedance of 8 ohms and their sensitivity is also same at 88 dB.
Sensitivity
Bookshelf Speakers
Power Range
Power
range is the range of input power in watts RMS that a loudspeaker is designed to handle. While using an amplifier within this range ensures the nominal performance , inputting a power that is higher than the max wattage can result in a damaged speaker.
Crystal 4.2 can handle a max power of 125 watts RMS from the amp the whereas Crystal 4.2 has a max power handling value of 100 watts RMS , 25 watts less than the S20.
Keep in mind that a higher max power handling value doesn't necessarily make that a louder speaker
compared to a lower max handling speaker. Loudness or the sound level is also impacted by parameters
such as Impedance, sensitivity and system efficiencies.
Input Type and Bi-Amping / Bi-Wiring
Crystal 4.2 features 5-way post type posts and S20 has a 5-way post type posts. None of these speakers feature bi-amping/bi-wiring.
Cabinet Type and Port Position
Both Crystal 4.2 and S20 have rear firing ports. Rear ported speakers generally need more room between the backside of the speaker and the wall compared to sealed and front/bottom ported speakers. Placing the speakers too close to the walls may cause the bass to sound boomy.
If you are limited in space and can't get the speakers away from the backwall, check our Speakers with Front Firing Ports page.
Physical Specs
Size of a speaker can sometimes become an important decision factor due to space constraints or in some cases purely for esthetic reasons. In this section, we are going to compare Wharfedale Crystal 4.2's and Polk S20's external dimensions. Wharfedale Crystal 4.2 has external dimensions of 266.0 x 181.0 x 220.0mm ( 10-7/16 x 7-1/8 x 8-5/8inch) whereas Polk S20 has external dimensions of 376.0 x 216.0 x 350.0mm ( 14.8 x 8.5 x 13.7inch) .
Polk S20 is clearly the larger of the two speakers. Its body is 35mm wider, 110mm taller and 130mm deeper than Wharfedale Crystal 4.2.
Base Surface Area Comparison
Base surface area of a loudspeaker may become a determining factor when the space in your room or desk is limited.
The base surface area of the Wharfedale Crystal 4.2 is approximately 398.2cm2 / 61.7inch2 and base area of the Polk S20 is approximately 756.0cm2 / 117.2inch2. The Crystal 4.2 requires 47% less surface area than the S20 which gives it a small advantage on placement in tight spaces.
Weight Comparison The weight of a loudspeaker can become an important factor if you need to move and reposition the unit often. Weight of a speaker can also "sometimes" be an indicator of the rigidity of the enclosure and the quality of the internal components used. The Wharfedale Crystal 4.2 weighs 4.20kg / 9.2lbs and the Polk S20 weighs 7.73kg / 17lbs. This makes the S20 84% heavier than the Crystal 4.2.
Here is a comparison of how Crystal 4.2 and S20's weights compare with the average, max and min weights in Passive Bookshelf class.
Weight
All Bookshelf Speakers
What's in the Box of Wharfedale Crystal 4.2?
Here are the items that are included inside the box of Crystal 4.2:
2 Bookshelf loudspeakers2 Grilles (pre-installed)User-feets ManualInstallation Guide
What's in the Box of Polk S20?
Here are the items that come with the S20:
2 Bookshelf loudspeakers2 Grilles (attached)8 Self-adhesive rubber feetOwners ManualOnline Product Registration
Height |
266mm
vs
376mm
|
Easier to fit in smaller spaces |
Base Surface Area |
398cm2 (181x220mm)
vs
756cm2 (216x350mm)
|
Takes less floor space |
Max Input Power |
125 watts
vs
100 watts
|
Handle more power from your amplifier |
Woofer Size |
6.5 inches
vs
5 inches
|
Larger woofer |
Low Frequency Response |
39 Hz
vs
60 Hz
|
Generates deeper bass |
High Frequency Response |
40k Hz
vs
20k Hz
|
Generates higher frequency |
General |
Wharfedale Crystal 4.2 |
Polk Audio Signature S20 |
Brand |
Wharfedale |
Polk Audio |
Speaker Type |
Bookshelf speakers |
Bookshelf speakers |
Power Range |
20-100 watts |
20-125 watts |
Sensitivity |
88 dB |
88 dB |
Impedance |
8 ohms |
8 ohms |
Frequency Response |
60-20k Hz |
39-40k Hz |
Drivers |
|
|
Woofer Quantity |
1 |
1 |
Woofer Size |
5" |
6.5" |
Woofer Composition |
Woven Kevlar |
Mica-reinforced polypropylene |
Woofer Surround Material |
Rubber |
Butyl rubber |
Tweeter Size |
1" |
1" |
Tweeter Type |
Soft-dome |
Soft-Dome |
Aimable Tweeter |
No |
No |
Midrange Driver |
No |
No |
Crossover Frequency |
n/a |
2500Hz |
Firing Direction |
rear |
rear |
Physical Specs |
|
|
Height |
266.0mm (10.5") |
376.0mm (14.8") |
Width |
181.0mm (7.1") |
216.0mm (8.5") |
Depth |
220.0mm (8.7") |
350.0mm (13.8") |
Weight |
4.20kg (9.2lbs) |
7.73kg (17lbs) |
Enclosure |
Bass reflex |
Bass Reflex |
Finish |
Wood-grain vinyl |
Meddite MDF |
Available Colors |
Walnut |
Black, Walnut, Brown Walnut |
Mounting Bracket |
No |
No |
Recommended Stand Height |
24-28" |
24-28" |
Grille |
Yes |
Yes |
Moisture Resistancy |
No |
No |
Connections |
|
|
Biamp Inputs |
No |
No |
Other |
|
|
Parts Warranty |
5 Years |
5 Years |
Labor Warranty |
5 Years |
5 Years |